Book shelf unit



FIG. 1 is a perspective view of a book shelf unit showing my new design;

FIG. 2 is an end elevational view of the book shelf unit of FIG. 1;

FIG. 3 is a side elevational view of the book shelf unit of FIG. 1;

FIG. 4 is a perspective view of a second embodiment of the book shelf unit shown in FIG. 1;

FIG. 5 is an end elevational view of the book shelf unit of FIG. 4;

FIG. 6 is a side elevational view of the book shelf unit of FIG. 4; and

FIG. 7 is a perspective view of a third embodiment of the book shelf unit shown in FIG. 1. 

The ornamental design for a book shelf unit, as shown and described. 